*5.3.4. Dermatophytes*

136 New Approaches to the Study of Marine Mammals

*5.3.1. Candida* 

**5.3. Fungal infections of cetacean skin**

pseudohyphae, septate hyphae and blastospores [16, 60].

reported in these mammals [60].

portions of the cetaceans' bodies [31].

*5.3.2. Fusarium* 

*5.3.3. Lacazia loboi* 

Species of *Candida* are commonly associated with the mucous membranes of animals in limited numbers, and occur predominantly in the regions of the blowhole, oesophagus, vagina and anal area in cetaceans [59-61]. *Candida* spp. reported from cetaceans include *Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Candida parapsilosis, Candida guiliermondii*, *Candida lambica* and *Candida ciferrii* [59, 60]. *Candida zeylanoides* was also found to be associated with the skin of a southern right whale neonate from South Africa [45]. Infections caused by *Candida* spp. mostly affect captive cetaceans and are usually associated with immuno-suppressed individuals, where the *Candida* infection may proliferate and cause severe local infection of the skin or mucosal membranes. In captive cetaceans, infections are usually observed after long-term antibiotic therapy [30, 61], but had also been reported following corticosteroid treatment of the animals, as well as after overtreatment of tank water [59]. These lesions usually occur as whitish, creamy plaques on the skin or mucosal surfaces. Histological examinations usually show colonies of

In cutaneous *Candida* infections, the skin or mucosal membranes, may suffer acanthosis (hyperplasia and thickening of the stratum spinosum) with pseudoepitheliomatous hyperplasia, with the fungus growing in the epithelial tissue. These cutaneous *Candida*  infections had been reported in a number of cases pertaining to especially captive cetaceans and varied from ulcerative dermatitis, to inflammation without ulcers and healed ulcers. However, significantly more cases of visceral lesions and systemic candidiasis had been

*Fusarium* spp. are well known saprophytes in soil, as well as the cause of a range of plant diseases. However, they also often cause hyalohyphomycosis after traumatic inoculation in humans and seem to be an emerging pathogen in immuno-compromised patients [16]. In cetaceans, mycotic dermatitis caused by a *Fusarium* sp., was reported in a pygmy sperm whale and an Atlantic white-sided dolphin. These cetaceans were characterized by elevated, firm, erythematous, cutaneous tubercles mostly found on the heads, trunks and caudal

The yeast-like, dimorphic fungus, *Lacazia loboi* (formerly known as *Laboa loboi*) causes invasive cutaneous lesions in dolphins and humans [58], known as lobomycosis, lacaziosis or keloidal blastomycosis [41, 59, 62]. The first case of keloidal blastomycosis was described in 1931 in a human patient from the Amazon valley [63]. This disease was only known to affect humans until 1971, when Migaki and co-workers described a case of lobomycosis in an Atlantic bottlenose dolphin [64]. In 1973, De Vries and Laarman [63] described another Dermatophytes are fungi that grow on the outermost layers of the skin of animals, including muco-cutaneous membranes, genitalia, external ears, as well as dead skin or hair. Ringworm presents one type of dermathophyte and includes the genera *Tinea, Trichophyton, Epidermophyton* and *Microsporum* [16]*.* Infections caused by dermatophytes, seem to be rare in marine mammals, and therefore also in cetaceans. Limited reports include discrete nodules on the back of a captive Atlantic bottlenose dolphin caused by a sp. of *Trichophyton* [60].
